Perform in vitro studies on cellular and humoral elements of the bovine immune systems on tissues provided by the Government from experimental animals involved in a study of immunoprophylaxis of bovine odular squamous cell carcinoma, in order to determine whether correlative changes in immune response can be detected during the process of cancer development, and if so, to determine the immunologic mechanisms involved. The work will be carried out in two phases. The first phase will represent a feasibility study for the development and selection of an appropriate number of relevant tests, subject to approval and acceptance by the Project Officer. The second phase will involve the application of the tests selected to the program objectives stated above.